Campbell Hausfeld SDM-CAN Manual Do Utilizador

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Appendix C.  Application of the         
SDM-CAN on Networks Complying with 
the J1939 SAE Standards. 
This Appendix describes the use of the SDM-CAN in applications where the CAN network 
complies to the J1939 standard, which is common in truck, bus and marine applications in the 
USA. This appendix is not intended to act as a full reference to those standards, but to simply 
describe the coding of the ID parameter and to give examples of how to decode some of the 
common, defined J1939 data packets. 
C.1  J1939 29-Bit Identifier Format  
The J1939 identifier format consists of 6 predefined fields; for a 29-bit identifier 
these are:
 
P - Priority Field (3 bits) 
R - Reserved Field (1 bit) 
DP - Data Page Field (1 bit) 
PF - PDU Format Field (8 bits) 
PS - PDU Specific Field (8 bits) 
SA - Source Address Field (8 bits) 
 
Table C-1  Mapping of the J1939 Fields into a 29-Bit Identifier 
Bi
t  28 
27 
26 
25 
24 23 
22 
21 
20 
19 18 17 16 15 14 13 12 11 10
9 8 7 6 5 4 3 2 1 0 
 P 


R
D
P

P

P

P

P

P

P

P

P

P

P

P

P

P

P

P

S

S

S

S

S

S

S

S

 
C.2  J1939 11-Bit Identifier Format  
The J1939 identifier format consists of 2 predefined fields; for an 11-bit identifier 
these are: 
P - Priority Field (3 bits) 
SA - Source Address Field (8 bits) 
Table C-2  Mapping of the J1939 Fields into a 11-Bit Identifier 
Bit 
10 9 8 7 6 5 4 3 2 1 0 
 P 


S

S

S

S

S

S

S

S

 
Details of identifier field values can be found in the SAE J1939 
standard. 
NOTE 
C-1